Compressor.



E. M. NIEBLING.

COMPRESSOR.

APPLICATION FILED [150.22.1915.

Patented July 17, 1917.

III/( wall/M EDWIN M. NIEBLING,

or CINCINNATI, oII o.

COMPRESSOR.

Specification of Letters Patent.

Patented July I7, rare Application filed. December 22, 1915. Serial No.68,119.

. To all whom it may concern:

Be it known that I, EDWIN M. NIEBLING, residing at Cincinnati, Hamiltoncounty, State of Ohio, have invented certain new and useful Improvementsin Compressors, of which the following is a clear, full, and

- exact description, attention being called to the drawing whichaccompanies this application and forms a part thereof.

This invention concerns pumps used for compressing fluids like gases orair. It rc-' latcs more partlcularly to pumps operating against heavypressure such as for instance occurs in refrigerating plants and wherethe pumps are used to manipulate the refrigerating agent. This isusually ammonia which, in form of expanded gas, is drawn into thecylinder of the pump through an opening controlled by a suction valve.It is then compressed by the piston of the pump and expelled throughanother opening in the cylinder controlled by a discharge valve.

In the interest of economical operation it is essential that most and ifpossible all the gas which is compressed ahead of the piston is expelledfrom the cylinder, otherwise, as soon as the piston starts on its returnstroke, any gas which remains will reexpand and reduce the capacity ofthe cylinder for receiving gasto be compressed by the next pistonstroke. In other words, part of the same charge of gas remains in thecylinder and is repeatedly compressed therein without producing anyuseful efl'ect.

In order to overcome any defects of this kind in the operation ofcompression pumps, it has been the aim to cause the piston to move asclose as possible against the discharge valve so-as to reduce and ifpossible prevent the presence of any dead spaces or pockets between theface of the piston and the discharge valve where gas may remain out ofoperative reach of the piston. This expedient is not applicable in allforms of valves used in compression pumps and particularly not in valvesof the types known as plate-valves, disk-valves or feather-valves andwhere certain features peculiar to their construction produce a gaspocket on one side of them. I

Otherwise valves of these types would be very satisfactory and in manycases preferable to the valves now used'in compres sion pumps operatingunder the conditions named.

Therefore the object of my invention is to provide certain means whichmake it possible to use valves of the types referred to on pumpsoperating under heavy pressurecondit'ions but without subjecting thisuse to the objections mentioned above.

The invention consists of certain features of construction which aredescribed hereinafter and pointed out in the claims.

The constru ction is also illustrated in the accompanying drawing, inwhich:

Figure 1 illustrates my invention as applied to a single-actingcompression-pump which is shown in vertical longitudinal section.

Fig. 2 is a section taken at right angle to the plane of sectionpresented in Fig. 1, and shows the valve-part of the compressor.

Fig. 3 is a top View of one of the valves shown in the preceding figure.

Fig. 4 in a view similar to Fig. 2, shows the same part of thecompressor with a valve of different type.

Fig. -5 is a top view of this valve with parts broken away.

,Fig. 6 illustrates part of a double-acting compression pump with thefeature of my inventionapplied to it.

The drawing shows conventional types of pumps merely for the purpose ofillustrating the invention.

Character A, indicates the provided with a water jacket indicated at aand B indicates the piston.

Referring to the' form shown in Fig. 1, the matter to be moved, expandedammonia gas for instance, enters at 10 and after compression is expelledat 11. This gas, on the lip-stroke of the piston, passes into thecylinder and when the piston moves down, it passes to the other side ofsaid piston which latter is hollow and controlled by a suitable valve 12of the suction-valve type. On the next lip-stroke of the piston the gasabove the latter is compressed and forced out of the end of thecylinder, said outlet being controlled by discharge valves provided inthe cylinder head. 1

Valves of various types are used in this connection. In some kinds ofpumps socalled feather-valves, as shown in Figs. 1 and 2, are used anddisk-valves, as shown in Figs. 4 and 5, have also been used.

In these types of valves the valve member proper is yieldingly confinedin a space provided between two superposed members which latter areprovided with 'openingsin front of the valve and back of the same toclear the matter passing. By reason of the presence of one of thesemembers on each side of the valve, the piston can move only as far asone of said members permits, but it cannot closely approach the valveand therefore not all of the gas after compression is forced beyond thevalve and out of the cylinder.

The openings in one of these members, the one which is between'the valveand the piston, form pockets in which compressed gas is retained and onreversal of the pistonmotion this gas reexpands and fills part of thecylinder, thereby reducing the receiving capacity of the same, andimposing unnecessary work upon the pump required by the repeatedcompression of the same gas. While such working conditions are obectionable in all cases for'the reasons stated,

the objection becomes more pronounced 'when pumps operate against heavypressure because the retained part of the highly compressed gas afterreleased from the pockets occupies a correspondingly larger part of thecylinder.

To overcome these objections I provide members which, as the pistonnears the end of 'itsstroke, enter these pockets on one side of thevalve and by doing so necessarily displace the gas therein and force it'out of them. By reason of their particular function these members arehereafter designated.

as displacers.

Referring now to Figs. 1, 2, 3 and 6, these displacers, indicated at 13,are shown .as used in connection with feather-valves, which latterareshown at 14:. These valves consist substantially of thin, elongatedblades of elastic metal, normally seated against seat-member 15, asshown in dotted lines, so as to close ports 16 therein. These valves areheld in place by another member 17 which engages them at their ends andis provided with ports 18. When the piston approaches the discharge endof the cylinder, the rising pressure of the gas flexes these blades asshown in Fig. 2, permitting the compressed gas to pass through ports 16,around the ed es of the blades into ports 18 and through t em tooutlet-11. Now under conditions when my improved construction is notused, the face of the piston, represented in this case by the closedsuction valve which-is carried in the piston, cannot approach the faceof the feather valves any closer than member 15 permits and as a resultcompressed gas remains pocketed in ports 16 which on the return of thepiston rexpands into the cylinder.

This objection is overcome by .Iny improved construction which Iprovides displacers 13 adapted to enter ports 16 so that practically.all the compressed gas is forced beyond feather valves 14.

These displacers consist of projections shaped substantially tocorrespond to the space which they are intended to occupy, allowance fornecessary clearance under working conditions being made.

In Fig. 6, part of a double-acting pump is shown using a double piston,the inlet 10 to the cylinder bein between the pistons and each end isprovi ed with an outlet.

One or more nests of feather valves are seated in the end of thecylinder, also in each piston, they being held in position 'by bushings19. Gas is drawn into the cylinder between the pistons at each stroke ofthem and also passes at each stroke alternately into one or the other ofthe spacesoutside of the pistons and through the valves in them whichact as suction valves.

As shown in Fig. 6 the pistons are presumed to move so that the pistonon the right compresses the gas between it and the end of the cylinderand forces the same out of the latter through the feather-valves carriedin said end. I e

To expel the gas in the pockets formed by ports 16 the samedisplacers 13are provided on the face of both pistons. It of course is also necessaryto displace the gas which occupies the pockets formed by ports 18 in thevalves carried in the pistons. This is accomplished by other displacers13 which are located in proper position so as to project from the end ofthe cylinder into these ports as the piston approaches the end of thecylinder.

Practically the same arrangement would be employed in a double-actingpump which operates with a single piston and where no valves areprovided in the piston, all valves being located in the ends of thecylinder, inlet valves as well as discharge valves. In that casedisplacers would be provided on both sides of the iston as is now shownon one side of the plstons illustrated in Fig. 6.

In that event it is immaterial whether the suction valves are of thefeather valve type, and instead they may be of the usual type as shownin Fig. 1, in which case of course, as to the suction valves, nodisplacers would be required.

The displacers provided by my invention are also applicable in caseswhere so-called plate or disk valves as shown in Figs. 4 and 5 are usedin place of the feather valves as they are shown for instance in Figs.1" and 6. The valves of this type consist of one or more ring-shapedplates of limited ing'respectively part of seat members 24. and 25 andeach of which members is se-. cured in a suitable manner to the valvehead 26. Springs 27, confined between-this head and plate valve 21 keepthis latter yield-' ingly seated against shoulders 22 and 23, being heldproperly while so moving by guides 28.

The port controlled by this plate valve is .formed by the annularopening or space 29 between these shoulders 22 and 23 and when this portis open, that is when valve 21 is raised as shown in Fig. 4, the gaspasses through this port, around the edges of valve 21 and through portopenings 31 in head 26. As will be seen, this port forms a pocket ordead space, inaccessible to the piston the,

same as do ports 16 in case of the feather valves shown in Fig. 1. Todisplace the gas in this pocket, I follow the same principle applied inthe case of the feather valves,

' that is to say, I provide displacers which conform to the requiredshape and carry out the same function for the same purpose in the samemanner. Accordingly the displacer is in form of an annular projection orridge 32 as shown in Fig. 4..

Thus when such plate valves take the place of the'feather valves shownin Figs.

1 and 6, the complementary displacers, correspondingly located, would beof the shape shown in Fig. 4.

. While broadly considered neither feather valves nor plate valves arenew with me, I have nevertheless devised certain improve ments in theconstruction of plate valves whereby their manufacture is simplified andwhich permits me to increase the port-capacity of the valves by having anumber of annular plates similar to and concentric with the single platevalve 21 now shown and without complicating the construction orencumbering the free area of the added ports. Thus for instance ifanother plate valve were to be added to a valve as shown in Fig. 4, itwould only be necessary to have a correspondingly larger valve head 26.

Annular member 25 would be provided with an additional shoulder aroundits out-' seat forming members.

side to form one of the two annular valve seats, the inner one, for theadded plate valve, and a member, similar to present member 25, onlylarger in diameter, would be attached to the head in the same placeWhere it is now to provide the outer annular seatshoulder.

These individual valve-seat-forming members are all secured to valvehead 26 by suitable means. The upper part of central member 24 mayassume the form of a bolt as shown and be secured by a nut Screws 34Lmay be used to attach the other Another annular displacing ridge similarto ridge .32 would be provided on the piston to displace the gas in theadded port.

Having described my. invention, I claim as newz members to this head.

2. In valve construction, the combination .of a valve-head provided withports, an-

nular, valve-seat-forming members concentrically spaced from each otherto form an.

annular port between them and secured to the valve-head with a spacebetween them and said head, an annular valve contained in said space andsprings to yieldingly hold this valve seated.

In testimony whereof, I hereunto affiX my signature this 18thday ofDecember, 1915, in the presence of two witnesses.

EDWIN M.- NIEBLING.

Witnesses C. SPENGEL, A. JoHNsoN.

